Donald W. McKay

The 2013 Canadian Hypertension Education Program recommendations for blood pressure measurement, diagnosis, assessment of risk, prevention, and treatment of hypertension.

We updated the evidence-based recommendations for the diagnosis, assessment, prevention, and treatment of hypertension in adults for 2013. This years update includes 2 new recommendations. First, among nonhypertensive or stage 1 hypertensive individuals, the use of resistance or weight training exercise does not adversely influence blood pressure (BP) (Grade D). Thus, such patients need not avoid this type of exercise for fear of increasing BP. Second, and separately, for very elderly patients with isolated systolic hypertension (age 80 years or older), the target for systolic BP should be < 150 mm Hg (Grade C) rather than < 140 mm Hg as recommended for younger patients. We also discuss 2 additional topics at length (the pharmacological treatment of mild hypertension and the possibility of a diastolic J curve in hypertensive patients with coronary artery disease). In light of several methodological limitations, a recent systematic review of 4 trials in patients with stage 1 uncomplicated hypertension did not lead to changes in management recommendations. In addition, because of a lack of prospective randomized data assessing diastolic BP thresholds in patients with coronary artery disease and hypertension, no recommendation to set a selective diastolic cut point for such patients could be affirmed. However, both of these issues will be examined on an ongoing basis, in particular as new evidence emerges.

The 2008 Canadian Hypertension Education Program recommendations for the management of hypertension: Part 1 - blood pressure measurement, diagnosis and assessment of risk.

OBJECTIVE To provide updated, evidence-based recommendations for the diagnosis and assessment of adults with hypertension. OPTIONS AND OUTCOMES The diagnosis of hypertension is dependent on appropriate blood pressure measurement, the timely assessment of serially elevated readings, degree of blood pressure elevation, method of measurement (office, ambulatory, home) and associated comorbidities. The presence of cardiovascular risk factors and target organ damage should be ascertained to assess global cardiovascular risk and determine the urgency, intensity and type of treatment required. EVIDENCE MEDLINE searches were conducted from November 2006 to October 2007 with the aid of a medical librarian. Reference lists were scanned, experts were contacted, and the personal files of authors and subgroup members were used to identify additional studies. Content and methodological experts assessed studies using prespecified, standardized evidence-based algorithms. Recommendations were based on evidence from peer-reviewed, full-text articles only. RECOMMENDATIONS Recommendations for blood pressure measurement, criteria for hypertension diagnosis and follow-up, assessment of global cardiovascular risk, diagnostic testing, diagnosis of renovascular and endocrine causes of hypertension, home and ambulatory monitoring, and the use of echocardiography in hypertensive individuals are outlined. Key messages in 2008 include continued emphasis on the expedited, accurate diagnosis of hypertension, the importance of global risk assessment and the need for ongoing monitoring of hypertensive patients to identify incident type 2 diabetes. VALIDATION All recommendations were graded according to strength of the evidence and voted on by the 57 members of the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. All recommendations reported here received at least 70% consensus. These guidelines will continue to be updated annually.

The 2011 Canadian Hypertension Education Program Recommendations for the Management of Hypertension: Blood Pressure Measurement, Diagnosis, Assessment of Risk, and Therapy

We updated the evidence-based recommendations for the diagnosis, assessment, prevention, and treatment of hypertension in adults for 2011. The major guideline changes this year are: (1) a recommendation was made for using comparative risk analogies when communicating a patients cardiovascular risk; (2) diagnostic testing issues for renal artery stenosis were discussed; (3) recommendations were added for the management of hypertension during the acute phase of stroke; (4) people with hypertension and diabetes are now considered high risk for cardiovascular events if they have elevated urinary albumin excretion, overt kidney disease, cardiovascular disease, or the presence of other cardiovascular risk factors; (5) the combination of an angiotensin-converting enzyme (ACE) inhibitor and a dihydropyridine calcium channel blocker (CCB) is preferred over the combination of an ACE inhibitor and a thiazide diuretic in persons with diabetes and hypertension; and (6) a recommendation was made to coordinate with pharmacists to improve antihypertensive medication adherence. We also discussed the recent analyses that examined the association between angiotensin II receptor blockers (ARBs) and cancer.

Amygdala kindling, anxiety, and corticotrophin releasing factor (CRF)

Wistar rats were kindled electrically in the anterior or posterior medial amygdala of the right hemisphere. One week after the fourth stage 5 seizure, anxiety was assessed in the elevated plus maze test. Anxiety levels of rats kindled in posterior medial amygdala were reduced relative to implanted controls, but not relative to unoperated controls. Kindling of the anterior medial amygdala increased anxiety relative to implanted and unoperated controls. The different effects of kindling on behavior were unrelated to any parameter of kindling. The stress of an ICV injection of saline increased anxiety in unkindled controls but reduced anxiety in anterior medial amygdala-kindled rats. Injection stress effects on behavior were blocked by 50 micrograms of alpha-helical CRF (the CRF receptor blocker). These findings suggest that CRF released by the stress of the injection procedure mediates the behavioral effects in both kindled and control rats. In contrast, injection of CRF (2 micrograms, ICV) has no greater effect than ICV saline in anterior medial amygdala kindled rats, whereas it was anxiogenic in unkindled rats. ICV vehicle and CRF reduce kindling-induced anxiety equally. These findings suggest that CRF released during the injection procedure saturates available CRF receptors. Finally, kindling did not alter basal plasma corticosterone levels. These and other findings suggest that the anxiety-modulating actions of CRF are at central CRF receptors.

A New Algorithm for the Diagnosis of Hypertension in Canada

Accurate blood pressure measurement is critical to properly identify and treat individuals with hypertension. In 2005, the Canadian Hypertension Education Program produced a revised algorithm to be used for the diagnosis of hypertension. Subsequent annual reviews of the literature have identified 2 major deficiencies in the current diagnostic process. First, auscultatory measurements performed in routine clinical settings have serious accuracy limitations that have not been overcome despite great efforts to educate health care professionals over several years. Thus, alternatives to auscultatory measurements should be used. Second, recent data indicate that patients with white coat hypertension must be identified earlier in the process and in a systematic manner rather than on an ad hoc or voluntary basis so they are not unnecessarily treated with antihypertensive medications. The economic and health consequences of white coat hypertension are reviewed. In this article evidence for a revised algorithm to diagnose hypertension is presented. Protocols for home blood pressure measurement and ambulatory blood pressure monitoring are reviewed. The role of automated office blood pressure measurement is updated. The revised algorithm strongly encourages the use of validated electronic digital oscillometric devices and recommends that out-of-office blood pressure measurements, ambulatory blood pressure monitoring (preferred), or home blood pressure measurement, should be performed to confirm the diagnosis of hypertension.

The effects of variable foraging conditions on common murre (Uria aalge) corticosterone concentrations and parental provisioning

This study investigated how total corticosterone concentrations, chick-feeding rates, and adult body mass changed with food availability from 1998 to 2000 in the same individually marked common murres (Uria aalge). Capelin, the main prey species, arrived inshore by the onset of murre chick hatching in 1998 and 1999 (prey match years); whereas in 2000, hatching began approximately 1 week before the capelin arrived inshore to spawn (prey mismatch year). Serum corticosterone concentrations were higher in the same individuals in the prey mismatch year than they were in either of the match years. Birds sampled before peak capelin spawning in the mismatch year had higher corticosterone levels than murres sampled after peak spawning. Murres with higher corticosterone levels had higher chick-feeding rates and less mass loss in the mismatch year (compared to the match year 1999) than birds with lower levels. Corticosterone levels did not differ between birds that had not foraged for at least 12 h (brooded chick overnight) and those that had, suggesting that short-term food deprivation did not affect corticosterone concentrations. Taken together, these findings suggest that the difference between years reflects a baseline shift in corticosterone levels, particularly in the high-quality birds that were able to increase both corticosterone concentrations and foraging effort.

Prolactin responses to infant cues in men and women: Effects of parental experience and recent infant contact

We used a longitudinal design to test whether parental experience differentially affects the development of prolactin responses to infant cues in men and women. Couples provided two blood samples at three tests, one test just before their babies were born, and two tests during the early postnatal period (n=21). Nine couples repeated the tests near the birth of their second babies. In the 30 min between the two samples, couples listened to recorded infant cries at the prenatal test and held their baby (fathers) or a doll (mothers) at the postnatal tests. Blood samples were analyzed for prolactin concentrations. Prolactin values were then related to sex and parity differences as well as to questionnaire data concerning emotional responses to infant cries and previous infant contact. We found that (1) prior to the birth of both the first and second babies, womens prolactin concentrations increased after exposure to infant stimuli, whereas mens prolactin concentrations decreased; postnatal sex differences varied with parity; (2) womens prolactin reactivity did not change significantly with parental experience; (3) the same mens prolactin concentrations decreased after holding their first newborns but increased after holding their second newborns; this change was not gradual or permanent; (4) men reporting concern after hearing recorded infant cries showed a different postnatal pattern of prolactin change after holding their babies than men not reporting concern; and (5) men who had little contact with their babies just prior to testing had a more positive prolactin response than men who had recently held their babies for longer periods. Although parental experience appears to affect mens prolactin responses, differences in reactivity were also related to patterns of recent infant contact and individual differences in responses to infant cues.

Home blood pressure monitoring among Canadian adults with hypertension: results from the 2009 Survey on Living with Chronic Diseases in Canada.

BACKGROUND Canadians with hypertension are recommended to use home blood pressure monitoring (HBPM) on a regular basis. OBJECTIVES To characterize the use of HBPM among Canadian adults with hypertension. METHODS Respondents to the 2009 Survey on Living with Chronic Diseases in Canada who reported diagnosis of hypertension by a health professional (n=6142) were asked about blood pressure monitoring practices, sociodemographic characteristics, management of hypertension and blood pressure control. RESULTS Among Canadian adults with hypertension, 45.9% (95% CI 43.5% to 48.3%) monitor their own blood pressure at home, 29.7% (95% CI 41.1% to 46.3%) receive health professional instruction and 35.9% (95% CI 33.5% to 38.4%) share the results with their health professional. However, fewer than one in six Canadian adults diagnosed with hypertension monitor their own blood pressure at home regularly, with health professional instruction, and communicate results to a health professional. Regular HBPM was more likely among older adults (45 years of age and older); individuals who believed they had a plan for how to control their blood pressure; and those who had been shown how to perform HBPM by a health professional - with the latter factor most strongly associated with regular HBPM (prevalence rate ratio 2.8; 95% CI 2.4 to 3.4). CONCLUSIONS Although many Canadians with hypertension measure their blood pressure between health care professional visits, a minority do so according to current recommendations. More effective knowledge translation strategies are required to support self-management of hypertension through home measurement of blood pressure.

The antianginal efficacy of isosorbide dinitrate therapy is maintained during diuretic treatment

To determine whether the use of a diuretic would maintain the antianginal efficacy of isosorbide dinitrate during 1 week of therapy.

Is usual measurement of blood pressure meaningful

BACKGROUND Standardized measurement of blood pressure is widely recommended but rarely applied in usual clinical practice. OBJECTIVE To determine the differences resulting from physicians using standardized and usual (casual) techniques for measurement of blood pressure. METHODS Blood pressures measured by a research nurse, ambulatory blood pressure monitoring and echocardiographic estimation of left ventricular mass index were used as standards for comparison. RESULTS Use of casual technique resulted in blood pressure readings higher than those obtained by standardized technique, namely 6.2 (3.1-9.3) systolic and 3.9 (2.4-5.4) diastolic mmHg [means (95% confidence intervals)], and readings that were more variable. Sixty-two patients (42%) were classified normotensive by standardized techniques but hypertensive by physicians casual technique. When standardized technique was used 22 patients (15%) were classified hypertensive but blood pressure readings in normal range were obtained by usual technique. Measurements obtained using standardized technique were less variable and were significantly correlated to left ventricular mass index. CONCLUSION Using standardized technique is important if one is to classify the blood pressures of patients correctly. Use of usual or casual technique results in higher, more variable readings that are not related to left ventricular mass index. Results of this study strongly support recommendations that standardized technique should be used for assessing the cardiovascular risk of all adult patients.